2013/8/1 Joshua Colp <[email protected]> > Larry Moore wrote: > >> On 31/07/2013 8:08 PM, Joshua Colp wrote: >> >>> Zoltán Fekete wrote: >>> >>>> Thank You Larry! >>>> >>>> I have discussed with my provider. They are not able to insert the >>>> T38MaxBitRate value into the sip answer. :( >>>> https://gist.github.com/**anonymous/6120148<https://gist.github.com/anonymous/6120148>(line >>>> 559) >>>> >>>> That means we are not able to passtrough T38 Faxes with any asterisk >>>> version at all? >>>> What do you mean? Am I able to modify and compile the source? Is it >>>> compicated? (I'm not a developer) >>>> >>> >>> Based on the SDP in your gist the remote implementation has given no >>> attributes with the T.38 stream which makes it pretty broken >>> (T38FaxRateManagement is mandatory) and fun. The two hard parts really >>> would be 1. Modifying Asterisk in a sane fashion to cope and 2. >>> Determining the exact settings to make the implementation happy. >>> Defaults as defined in the spec are fine and good, but my experience has >>> taught me to throw those out the window when it comes to actual >>> implementations. >>> >>> >> It would seem that having a configurable option would be an idea for >> this scenario. >> > > That implies it would solve the problem, which my gut and experience tells > me... it wouldn't. I think the T.38 implementation is just cobbled together > and without knowing exactly how it behaves getting it to work would likely > be a nightmare (trust me, I've spent time in those deep dark reaches). > Throwing assumptions and defaults at it to try to make it work is of course > an option. > > My testing with Asterisk 1.8 and T.38, I obserevd that setting >> FAXOPT(minrate) or FAXOPT(maxrate)had no effect, I concluded that when >> Astrerisk is receiving it uses hard coded values - is this a sane thing >> to do?! >> > > When Asterisk is receiving the stack implementation offers what it wants, > with the ability to override. So Asterisk doesn't hard code those values, > the stack provides them. What is hard coded is the default values if none > are received. > > I would even say it's a bug that the negotiation doesn't fail, since the > remote side isn't providing a mandatory attribute. > > -- > Joshua Colp > Digium, Inc. | Senior Software Developer > 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA > Check us out at: www.digium.com & www.asterisk.org > > -- > ______________________________**______________________________**_________ > > Yes you're right! As I know FAXOPT() value affect only when asterisk woks as gateway. We need passtrouh because my endpoints and also my provider supports T38.
https://wiki.asterisk.org/wiki/display/AST/T.38+Fax+Gateway "Using T.38 Gateway mode T.38 Gateway mode should be used when one leg of a call is not capable of T.38 mode. In the event that both legs are capable and Gateway mode is configured, then the Gateway will step out of the way, allowing *transparent T.38 passthrough*." The main problem is that I can't use G711 for the entire fax session because the endpoints has 20-30ms response time. When I try to use my Asterisk as FAXOPT gateway (endpoint leg T38 and provider leg G711) can I force somehow to not accept the T38 re-INVITEs from the provider? They have ~1ms response time, so G711 on that leg would be fine but they also detect fax CED tones and sends the re-INVITEs. Regards, Blaxy
-- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
